[server][fix]: add sub to userinfo

Resolves: #327

server/handlers/userinfo.go

@@ -1,6 +1,8 @@
 package handlers
 
 import (
+	"encoding/json"
+	"fmt"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
@@ -39,7 +41,28 @@ func UserInfoHandler() gin.HandlerFunc {
 			})
 			return
 		}
-
+		apiUser := user.AsAPIUser()
-		gc.JSON(http.StatusOK, user.AsAPIUser())
+		userBytes, err := json.Marshal(apiUser)
+		if err != nil {
+			log.Debug("Error marshalling user: ", err)
+			gc.JSON(http.StatusUnauthorized, gin.H{
+				"error": err.Error(),
+			})
+			return
+		}
+		fmt.Println("=> str:", string(userBytes))
+		res := map[string]interface{}{}
+		err = json.Unmarshal(userBytes, &res)
+		if err != nil {
+			log.Debug("Error un-marshalling user: ", err)
+			gc.JSON(http.StatusUnauthorized, gin.H{
+				"error": err.Error(),
+			})
+			return
+		}
+		// add sub field to user as per openid standards
+		// https://github.com/authorizerdev/authorizer/issues/327
+		res["sub"] = userID
+		gc.JSON(http.StatusOK, res)
 	}
 }